add docker setup stage

Author: arnasbr

.github/workflows/tests.yml

@@ -30,6 +30,9 @@ jobs:
         with:
           persist-credentials: false
 
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
       - name: Copy .env
         run: cp .env.example .env